Interleaved Half-Bridge Flyback Converter With Zero-Current Switching

• Published in: IEEE transactions on power electronics Vol. 34; no. 4; pp. 3370 - 3383
• Main Authors: Liang, Tsorng-Juu, Cheng, Ming-Hsien, Huang, Wen-Yu, Tseng, Wei-Jing
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.04.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Buck converters; Capacitors; Circuits; Clamps; Converters; Design for recycling; Electric bridges; Electric potential; Electronics; Full load; Half-bridge flyback converter; Inductance; Leakage; Switches; Switching; Switching loss; turn-<sc xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">off switching losses; Zero current switching; Zero voltage switching; zero-current switching (ZCS); zero-current transition (ZCT)
• ISSN: 0885-8993; 1941-0107
• DOI: 10.1109/TPEL.2018.2852332

Conventional interleaved half-bridge flyback converters can recycle the leakage energy stored in leakage inductance to clamp the voltage across the main power switches at a dc input voltage. However, such converters still suffer from high switching losses, especially turn- off losses. In this paper, a novel turn- off zero-current-transition (ZCT) circuit is proposed for reducing the turn- off switching losses. The proposed ZCT interleaved half-bridge flyback converter operates at a fixed frequency without increasing the voltage stresses of the main switches. To verify the design, a laboratory prototype is implemented with 100 kHz, an input voltage of 400 V, and an output voltage of 24 V/480 W. The experimental results reveal that the proposed converter at full load and 20% load has efficiencies of 93.05% and 89.06%, yielding efficiency improvements of 1.17% and 4.12%, respectively, compared with the conventional interleaved half-bridge flyback converter.